JP3244751B2 - Image recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus for performing serial recording.

BACKGROUND ART Conventionally, an image recording apparatus for performing serial recording is configured as shown in FIG. At the bottom of the image recording apparatus main body 1, a cassette 3 in which a plurality of sheet materials 2 are stacked is arranged. In FIG. 26, a carriage 5 on which the recording head 4 is mounted is disposed on the left side, and a platen 6 is disposed below the recording head 4.

The recording head 4 is an ink jet type head for recording on the sheet material 2,
At the front end, there are m ink ejection ports 16 shown in FIG. 27. Although not shown, an ink chamber is provided inside, and ink droplets are ejected from the m ejection ports 16 in accordance with an image signal. Also,
Although not shown, a carriage drive motor is connected to the carriage 5 via a timing belt, and the carriage 5 reciprocates along the guide shaft 5a by the carriage drive motor.

[0004] To link the records of each line normally,
High precision is required for the feeding accuracy of the sheet material 2 by the transport lower roller 7. For this reason, the outer diameter of the lower transport roller 7 is accurately finished, and a pulse motor having high stopping accuracy is used as a driving device, and the rotation angle is controlled by a pulse.

In the recording apparatus, when the paper feed roller 11 is rotated by a feed signal, only the uppermost one of the sheet materials 2 is separated and sent out between the paper feed guides 9 and 10.

Next, the sheet material 2 is fed to the paper feed guides 9, 10
And is conveyed and sandwiched between a lower conveying roller 7 rotated by a drive motor (not shown) and an upper conveying roller 8 which is driven to rotate by the lower conveying roller 7.

At this time, in the sheet, the sensor arm 19-1 is in the state shown by the solid line in FIG. 26, and in the transmission type sensor 19-2 including the light emitting section and the light receiving section, the light from the light emitting section reaches the light receiving section. I do. During the non-detection of the sheet, the sensor arm 19-1 is in the state shown by the broken line, and the light from the light emitting unit is blocked by the sensor arm. By this state change, the paper sensor 19 including the sensor arm 19-1 and the transmission sensor 19-2 detects the trailing edge of the sheet.

Next, the sheet material 2 is further guided by pulling upper and lower rollers 12 and 13 through the platen 6 by the conveying force of the lower conveying roller 7 and the upper conveying roller 8, and the leading end of the sheet material 2 is pulled by the upper and lower rollers 12 and 13. Once stopped, it stops once.

The lower pulling roller 12 rotates in conjunction with the lower conveying roller 7, but the conveying amount is set slightly larger, and
Since the holding force of the sheet material 2 is weaker than that of the conveying upper and lower rollers 7 and 8, an appropriate tension acts on the sheet material 2 so that the sheet material 2 is not loosened.

In this state, the recording head 4 is moved by the carriage 5 from the near side to the far side in FIG. 24 to eject ink in accordance with an image signal to record a predetermined width (recording width) on the sheet material 2. Do. The recording width W is mxd, where d is the dot diameter and m is the number of ink ejection ports.

Each time one row of recording is completed, the sheet material 2 is stepped by the transport lower roller 7 by the transport lower roller 7 and the transport upper roller 8 by the transport lower roller 7 to print the next row. FIG. 28 shows details of the transport mechanism.

By repeating the above operation, recording is performed on the sheet material 2 and the trailing edge of the sheet material 2 is detected by the paper sensor 19, and the trailing edge of the sheet material is moved by the transporting upper and lower rollers 7,
At the time of step feed exiting from step 8, there is a portion which is fed only by the pulling upper and lower rollers 12 and 13. In order to prevent the sheet material from being fed too much, the rotation angle of the driving motor is reduced and the feed amount is adjusted. It has also been considered to reduce the number of ink ejection ports for actually ejecting ink and adjust the connection of recording in each step.

When the recording of one sheet of the sheet material is completed, the sheet material 2 is discharged from the pulling upper and lower rollers 12 and 13 onto the sheet discharge tray 14.

[0014]

However, in the above construction, the adjustment of the rotation angle of the drive motor and the adjustment of the ink ejection port at the time of the step feed in which the sheet material comes off from the conveying upper and lower rollers 7 and 8 are performed in order to improve the joining accuracy. This must be done, but it is necessary to detect the exact remaining amount from the conveying upper and lower rollers 7 and 8 at the rear end of the sheet material.

For this purpose, the number of step feeds of the sheet material by the conveyance roller from the start of recording is counted, and the number of step feeds until the trailing edge of the sheet material comes out of the paper sensor is determined. However, since the remaining amount of the rear end of the sheet material is determined based on the detection, the following disadvantages are caused.

In the case where a non-standard sheet material is accidentally pulled out of the paper sensor by the same number of step feeds as a standard-size sheet material, or even in a standard size A5 size (148 × 210 mm)
And 5.5 inch 8.5 inch (139.7 ×
215.9 mm) (in this case, 5.9 m
If m) is smaller than the feed amount of one step, the trailing edge may be detected by the paper sensor with the same number of step feeds, and it becomes impossible to perform optimal control corresponding to the remaining amount at each trailing edge. .

An object of the present invention is to solve the above-mentioned problems and to provide an image recording apparatus capable of performing high-precision recording.

[0018]

To achieve the above object, the present invention provides a head mounting means for mounting a recording head for recording an image on a sheet material, and a sheet upstream of the recording head. First transport means for transporting the material,
A second conveying unit that is arranged downstream of the recording head and conveys the sheet material by a conveying amount different from the conveying amount of the first conveying unit; An image recording apparatus for performing recording by sequentially repeating step conveyance of a sheet material having a constant width by the first conveyance means and the second conveyance means, wherein the first detection means detects a width of the sheet material; Detecting a rear end of a sheet material conveyed by the first conveying means and the second conveying means on the upstream side of the first conveying means.
Detecting means, the width of the sheet material detected by the first detecting means, the number of times of the step conveyance until the trailing edge of the sheet material is detected by the second detecting means after the start of recording on the sheet material, And a determining means for determining which standard size the sheet material is based on, the remaining amount of the trailing end of the sheet material is determined from the determined fixed size of the sheet material, and And control means for changing the amount of conveyance by the second conveyance means and the recording area of the recording head.

[0019]

[0020]

[0021]

[0022]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of an image recording apparatus according to a first embodiment of the present invention, and FIG. 2 is a sectional view of an apparatus main body. 26 and 28, the same components as those in FIGS. 26 and 28 are denoted by the same reference numerals, and 17 is a paper width sensor, which is composed of a reflection type sensor. The sheet material is provided on the carriage 5 and is conveyed to the platen 6 for recording. The carriage 5 once reciprocates on the sheet material before starting the process, and then detects a certain range of the sheet material. This limits the range in which ink is ejected, prevents ink from being ejected to portions where there is no sheet material, and prevents contamination of the apparatus.

FIG. 4 is a block diagram showing a control unit of the recording apparatus shown in FIG.

In the figure, reference numeral 101 denotes an up counter,
The pixel clock is counted up and reset by the pixel block clock. The pixel block clock indicates an effective area of the image data, and corresponds to 128 pixel clocks. Reference numeral 102 denotes a register in which a print dot position correction value is set by the CPU 106. A comparator 103 compares the count value of the up counter 101 with the print dot position correction value set in the register 102. As a result of the comparison, if they are equal or the count value is larger, an output X is output. 104 is an AND gate, which is a comparator 103
And an AND operation of the output value, the pixel clock, and the pixel block clock. Reference numeral 100 denotes a FiFo memory for temporarily storing image data, in which the image data is written in synchronization with the pixel clock and read out in synchronization with the output signal of the AND gate 104. An image memory / head driving unit 105 stores the image data from the FiFo 100 and drives the recording head based on the stored image data. Reference numeral 108 denotes a pulse motor that scans the recording head, and 109 denotes a pulse motor (hereinafter, drive motor) that performs paper feed. A motor driving unit 107 drives the pulse motors 108 and 109 based on the trailing edge amount obtained by detecting the trailing edge of the sheet material by the paper sensor.

In this embodiment, dot diameter d: 0.0635 mm Number of ink ejection ports m: 128 Recording width W (= m × d): 8.128 mm Number of pulses required to increase recording width W: 96 pulses 1 Transport amount t (= W / n) by the transport roller in pulses:
Approx. 0.0847 mm / pulse Conveyance amount ratio of pulling rollers 12 and 13 to conveyance rollers 7 and 8: 1.01 Conveyance amount of sheet material by conveyance rollers at the start of recording: 20
mm Distance from the transport rollers 7, 8 to the detection point of the sensor arm 19-1 a: 10.128 mm Distance from the transport rollers 7, 8 to the ink ejection unit: 11 m
m.

Next, a method of conveying the sheet material 2 will be described in detail.

The sheet material 2 is fed by 20 mm by the conveying upper and lower rollers 7 and 8 and stopped. The state shown in FIG. 3 is reached, and the operation for detecting the width of the sheet material 2 is performed. After that, each time the recording head 4 completes recording of one line by the recording head 4, the conveying lower roller 7 has the same amount as the recording width W of 8.128 m.
m. Thereafter, this operation is repeated to record on the sheet material 2. Sheet material 2 by paper sensor 19
When it is detected that the trailing edge of the sheet material has come to the vicinity of the transport lower roller 7, the size of the sheet material is determined based on the paper width performed as described above and the number of transport steps until the paper sensor 19 detects the trailing edge of the sheet material. I do. FIG. 5 shows the width corresponding to the sheet material of each size, the number of paper feeding steps until the paper sensor 19 detects the trailing edge, and the remaining amount of the sheet material from the conveyance roller 7 when the paper sensor is detected. .

For example, if the width is 210 mm and the number of steps up to the detection of the trailing edge by the paper sensor 19 is 33, the A4 size is determined, the drive motor control suitable for the trailing edge remaining 8.776 mm, and the ink ejection port Control the number.

The control of the number of drive motors and the number of ink ejection ports is performed as described in Japanese Patent Application No. 2-272394. In this embodiment, (1) the number of drive pulses of the drive motor is 96 pulses, the print dot position is corrected to 0 dots (no correction), (2) the number of drive pulses of the drive motor is 95 pulses, the print dot position is corrected to 1 dot, and (3) the drive motor is fed. Four pulses 94 pulses Print dot position correction 2 dots (4) Number of drive motor feed pulses 93 pulses Print dot position correction 3 dots (5) Number of drive motor feed pulses 95 pulses Five types of print dot position correction 0 dots Do.

For example, in the control (2), the number of feed pulses of the drive motor 109 is normally 96 pulses, but is set to 95 pulses, the feed amount at the time of step feed is set to 95/96 of the normal, and This is to prevent the ejection of one nozzle on the most downstream side from being performed.

The other controls also control the number of feed pulses of the drive motor and the ink ejection ports in the same manner as the control (2).

In FIG. 6, when the above five types of control are performed, the remaining amount of the rear end of the sheet material from the lower roller 7 is plotted on the abscissa, and the error of the splicing of the recording is plotted on the ordinate. An error indicates a state in which a gap is formed between dots, and a negative error indicates a state in which dots overlap. Then, a control method having the least error is selected from these five types according to the remaining amount at the rear end, and recording is performed.

For example, if it is determined that the sheet material is A4 size, the remaining amount at the rear end is 8.776 mm.
Control of the next step feed is 8.1 in the same manner as in (1).
Recording is performed using 128 nozzles with a feed of 28 mm. At this time, the remaining amount at the rear end is 8.776 mm to 8.128 mm.
648 mm, and then the control of (4) is performed to obtain an error of about 0.
A recording of 009 mm is made. In the subsequent recording, the trailing edge of the sheet material completely disengages from the transport lower roller 7 and the pulling lower roller 12
Since the sheet is fed only by the rear end, it is possible to perform recording with an error of about 0.004 mm by the control of (5) in the same way as in the case where the remaining amount at the rear end is 0. Since the paper is fed by about 15.4 mm and reaches the recording unit, it cannot be performed, and the recording ends. If the width is 148 mm and the number of times until the trailing edge is detected by the paper sensor is 23, A
5 size, and the trailing end remaining amount is 3.056 mm.
In this case, the error of about 0.
A 007 mm recording is made.

In this embodiment, since the gap between the lower conveying roller 7 and the ink discharge section is 11 mm, when the rear end of the sheet material is separated from the lower conveying roller 7 and fed by about 2.96 mm or more,
The recording in the next step cannot be performed because the recording unit comes off the sheet material. If the width is 139.7 mm and the number of times until the trailing edge is detected by the paper sensor 19 is 23 times, 5.
5 x 8.5 inch, rear end remaining amount is 8.956m
m. In this case, in the next step, the control without correction of (1) is performed to feed 8.128 mm, and the trailing end remaining amount at this time is 0.828 mm. Here, the control of (4) can be performed to perform recording with an error of about 0.007 mm.
For 5.5 × 8.5 inch size and A5 size sheets, the number of steps up to the paper sensor detection is 23, which is the same,
The remaining amount at the rear end is 8.956 mm and 3.056 mm, and the optimum control is different. This determination is made by detecting the width. Similarly, the remaining amount of the rear end of the sheet material of other sizes is detected based on the width of the sheet material and the number of feeding steps until the paper sensor 19 detects the rear end, and as shown in FIG. The control most suitable for the amount is performed, and the joining is recorded with high accuracy.

FIGS. 7 and 8 are flowcharts showing the control procedure of the present apparatus performed by the CPU 106. In step S201, a copy start command is waited. When the start command is received, in step S202, the sheet material is conveyed from the lower conveying roller 7 to a position 20 mm away.
At 3, wait for the end of paper feeding. Thereafter, in step S204, the pulse motor 108 is driven to scan the carriage 5, the sheet width sensor 17 detects the width of the sheet material, and determines a standard size, and enters a copy mode corresponding to each size (step S205). Transition. Step S20
In step 5, recording control corresponding to each standard size is performed.

FIG. 7 shows a control procedure for the A4 size copy mode. First, in step S210, the carriage 5 is moved to discharge ink from the ink discharge unit to record the first line, and in step S211 the paper sensor 19 is turned on or off.
Determine whether it is FF. If the paper sensor 19 is OFF (sheet is not detected), it is not the A4 size, so the process ends, and the process proceeds to the paper discharge subroutine of step S206 in FIG. If the paper sensor 19 is ON (sheet detection) in step S211, step feed of 96 pulses of the drive motor is performed in step S212, and then recording of the second line is performed in step S213. Next, it is determined whether the paper sensor 19 is ON or OFF.
If so, the process ends as in step S211 and step S2
The process proceeds to a paper discharge subroutine at 206, and if it is ON, a step feed of 96 pulses of the drive motor 109 is performed at step S215. Thereafter, in step S214, the paper sensor 19
S213 → S21 until becomes OFF or n = 33
4 → Recording is continued by repeating the processing of S215, the recording of the 34th line is performed in step S216, and thereafter, it is detected in step S217 whether the paper sensor 19 is ON or OFF. And OF
If it is F, it can be confirmed that the size is A4 size, so that the stepping of 96 pulses of the drive motor 109 is performed in step S218, and the recording of the 35th line is performed in step S219. Next, as control (4), step S220
Then, the drive motor 109 performs 93 pulse feed, and then the 36th line for three-pixel correction in step S221 is printed, and the processing is terminated. Then, the process proceeds to the sheet discharge subroutine of step S206 in FIG.

At step S206, the paper discharge operation is performed, and at step S207, the end of the paper discharge is waited.
In step S8, it is determined whether or not the copy is continuous copy. If the copy is continuous copy, the process proceeds to a paper feed subroutine of step S202.

In FIG. 8, the paper width is set to A4 in step S204.
However, the same applies to the case where it is determined that the width is other than the standard size, the number of lines in step S213 to be performed, the number of lines to be recorded in step S216, and the subsequent steps. S218-S
The other operations are the same except that the control of the paper feeding and the recording of 221 differs depending on each size.

(First Reference Example) Next, a first reference example of the present invention will be described with reference to FIGS. In the first embodiment, the image recording apparatus using only the fixed size sheet material has been described .
In the reference example , a non-standard size can be used.

FIG. 9 is a view showing a schematic configuration of an image recording apparatus according to a first reference example .
The distance to the detection point 9-1 is 14.055 mm. Other configurations are the same as those of the first embodiment.

FIG. 10 shows the width corresponding to the sheet material of each size in the first reference example, the number of paper feed steps until the sheet material is detected by the paper sensor 19, and the sheet material at the time of detecting the rear end of the sheet material by the paper sensor 19. 5 shows the remaining amount from the transport lower roller 7.

In the case of a sheet of a fixed size, optimal control is performed in the same manner as in the first embodiment based on the width and the number of steps up to the detection of the trailing edge from the table in FIG.

FIG. 11 shows the relationship between the remaining amount at the rear end and the joining error in each control in the first reference example .
Here, the line at the trailing end with the remaining amount of 5.927 mm indicates the detection point of the paper sensor 19-1. The actual detection point is 14.55 mm from lower roller 7
However, in order to make the explanation easy to understand, it is shown at a position shifted by a feed amount of 8.128 mm for one step.

Here, when a non-standard sheet material is conveyed, the width of the sheet material and the number of steps until the sheet sensor 19 detects the rear end of the sheet material do not match the relationship shown in FIG. In this case, when the paper sensor 19 detects the rear end, the remaining amount x at the rear end is 5.927 ≦ x <14.055. This next step feed is performed under the normal control of (1).
Send 128mm.

In this state, the remaining amount x at the rear end is -2.20.
1 ≦ x <5.927. Here, when x is negative, the rear end is located downstream of the transport lower roller 7 and the transport lower roller 7
, And is fed by the pulling roller 12. Therefore, when the remaining amount x at the rear end is in the range of 0 ≦ x <5.927 at the end of this step, the joining error becomes 0, and −2.201 ≦ x <0, that is, the paper sensor 19 detects the sheet material. Rear end remaining amount x when rear end is detected
Is 5.927 ≦ x <8.128, the error in the range of 5.927 ≦ x <8.128 in the control (1) shown in FIG. 11 is 0 to 22.01 μm. Then, the control of (3) is performed in the next step. When the remaining amount x at the rear end at the time of performing the control of (3) satisfies −2.201 ≦ x <0, FIG.
Error is 37.25 μm and 0 ≦
When x <5.927, the error is −22.02 μm to 37.2.
It is in the range of 5 μm.

As described above, even in the case of a non-standard size sheet material, the detection point of the paper sensor 19 is set to an appropriate position, and the control is performed by determining the non-standard size according to the width of the sheet material and the number of steps for the paper sensor 19 to detect the rear end. By performing the above, recording can be joined with a small error.

FIGS. 12 to 14 are flowcharts showing the control procedure of the device embodying the first embodiment. In step S301, a copy start command is waited. When the start command is received, in step S302, the sheet material is conveyed to a position 20 mm from the lower conveying roller 7, and in step S303, completion of sheet feeding is waited. Thereafter, in step S304, the pulse motor 108 is driven to scan the carriage 5, the sheet width sensor 17 detects the width of the sheet material, determines which standard size is used, and shifts to a copy mode (step S305) corresponding to each size. I do. In step S305, printing control corresponding to each standard size is performed. If the size is an irregular size, the mode shifts to an irregular size mode described with reference to FIG.

FIG. 13 shows a control procedure for the A4 size copy mode. First, in step S310, the carriage 5 is moved to eject ink from the ink ejection unit to record the first line, and in step S311, the paper sensor 19
Is determined to be ON or OFF. If the paper sensor 19 is OFF, that is, if the sheet material is not detected, it is not the A4 size, so it is determined to be non-standard size, and the control is shifted to 96 pulse feed of the drive motor 109 in step S326 as non-standard size control. At step S311, the paper sensor 19
If N, that is, if the sheet material is being detected, the drive motor 109 performs step feed of 96 pulses in step S312, and then records the second row in step S313. Next, it is determined whether the paper sensor 19 is ON or OFF.
If it is F, the size is determined to be an irregular size as in step S311, and the process proceeds to step S326. If it is ON, step feed of 96 pulses of the drive motor 109 in step S315 is performed. Thereafter, in step S314, the paper sensor 19
S313 → S31 until is turned off or n = 33
4 → Recording is continued by repeating the process of S315, the recording of the 34th line is performed in step S316, and then it is detected in step S317 whether the paper sensor 19 is ON or OFF. Rear end is paper sensor 1
9 has not yet been reached, and a normal 96
Performs pulse step feed. And then step S3
At step 23, the recording of the n-th line (35 ≦ n) is performed. At step S324, it is determined whether the paper sensor 19 is OFF or ON.
If N, paper feeding of the next 96 pulses is performed in step S325, and the flow returns to step S323 to perform recording. In step S324, the control is continued until the paper sensor 19 is turned off. After the paper sensor 19 is turned off, the control of the drive motor 109 in step S326 is performed as control (1) of the rear end for the non-standard size.
Six pulse steps are performed, and then step S327 is performed.
Perform normal recording with. Then, as the control (3), the drive motor 94 pulse is sent in step S328, the two-pixel correction is recorded in step S329, and the process proceeds to the sheet discharge subroutine in step S306. If the paper sensor 19 is turned off in step S317, A
It is determined that the size is four, and step S21 of the first embodiment is performed.
The same control as in steps 8 to S221 is performed in steps S318 to S32.
Then, the process proceeds to step S306.

If it is determined in step S304 that the size is irregular, the control shown in FIG. 14 is performed. First, in step S330, the carriage 5 is moved to discharge ink from the ink discharge unit, and recording of the first line is performed. In step S331, it is determined whether the paper sensor 19 is ON or OFF. If it is OFF here, the control of the rear end is performed in step S
336, and if ON, the rear end is still the paper sensor 19
Since it has not come, the normal step feed of 96 pulses is performed in step S332.

Then, at step S333, n (2 ≦
n) The recording of the line is performed, and it is determined whether the paper sensor 19 is OFF or ON in step S324. If the paper sensor 19 is ON, the paper is fed for the next 96 pulses in step S335, and the process returns to step S333 and performs recording again. In step S334, the process is continued until the paper sensor 19 is turned off. After the paper sensor 19 is turned off, the rear end control (1) for the non-standard size is performed in step S334.
At step S337, 96 pulses of the drive motor 109 are fed, and then at step S337, normal recording is performed. Then, as a control (3), a step feed of 94 pulses of the drive motor 109 in step S338 is performed, and recording of two-pixel correction is performed in step S339.
To the paper discharge subroutine, and performs the paper discharge operation. In step S307, the process waits for the end of paper discharge, and after the end, proceeds to step S3.
In step 08, it is determined whether or not continuous copying is performed. If the continuous copying is performed, the process proceeds to the sheet feeding subroutine of step S302.

In both the first embodiment and the first reference example , the sheet material is fed vertically, but when the sheet material fed horizontally is also included, for example, the vertical feeding of A4 size and A5 size Are 210 mm in width. The number of steps for the trailing edge detection is 33 and 15 in the first embodiment. Therefore, if the width is 210 mm and the number of steps is 33, the A4 size vertical feed is performed. If the width is 210 mm and the number of steps is 15, the number of steps is 15.
If the number of times is equal to the number of times, it is determined that the feed is A5 size and the optimal control is performed.

In the above-described embodiment, the control is performed using the number of paper feed steps until the paper sensor 19 is turned off.
Control may be performed using the time until 9 is turned off.

As described above, the conveyance amount of the sheet conveying means and the recording area of the recording means depend on the width of the sheet material detected and the number of step conveyances by the sheet conveying means until the trailing edge of the sheet material is detected. By providing a control means for changing either or one of them, there is an effect that high-precision image recording can be performed even at the end of the sheet material.

Second Embodiment Next, a second embodiment of the present invention will be described. Second participant
In the example , the number of all the ink ejection ports of the recording head 4 is set to be larger than the number of the ink ejection ports actually used for recording, and the number of all the ink ejection ports of the recording head before and after passing through the transport upper and lower rollers. (Also referred to as a jetting element) to change the range of use so that a blank portion does not occur between lines so that accurate joining is performed.

FIG. 15 is a diagram showing a schematic configuration of an image recording apparatus according to the second reference example . Reference numeral 101 denotes an image recording apparatus main body, and a cassette 1 in which a plurality of sheet materials 102 are stacked at the bottom thereof.
03 is arranged. Further, on the left side of FIG. 15, a carriage 105 on which the recording head 104 is mounted is arranged, and below the recording head 104, a platen 106 is arranged.

Here, the recording head 104 is an ink jet type head that ejects ink droplets by causing a state change in the ink by using thermal energy to perform recording on the sheet material 102. An ejection element 116 shown in FIG. 16 has m nozzles at the end, and although not shown, an ink chamber is provided inside, and ink droplets are ejected from the m ejection elements 116 in accordance with an image signal. Although not shown, the carriage 105
A carriage drive motor is connected via a timing belt, and the carriage drive motor reciprocates along the guide shaft 105a.

In order to connect the recordings of the respective rows normally, high precision is required for the feeding accuracy of the sheet material 102 by the lower conveying roller 107. For this reason, the transport lower roller 107 is finished with an accurate outer diameter, and uses a pulse motor with high stopping accuracy as a driving device, and controls the rotation angle by a pulse.

In the recording apparatus, when the paper feed roller 111 is rotated by the feed signal, only the uppermost sheet of the sheet material 102 is separated and sent out between the paper feed guides 109 and 110.

Next, the sheet material 102 is
9 and 110, which are rotated by a drive motor (not shown).
7, the sheet is fed and nipped between the upper roller 108 and the conveying roller 108 which is driven to rotate.

Next, the sheet material 102 is further guided by pulling upper and lower rollers 112 and 113 through the platen 106 by the conveying force of the lower conveying roller 107 and the upper conveying roller 108, and the leading end of the sheet material 102 is pulled by the upper and lower rollers 11.
When it is sandwiched between 2, 113, it stops once.

The lower pulling roller 112 is the lower conveying roller 10.
It rotates in conjunction with 7, but the transport amount is set slightly larger,
In addition, the pinching force of the sheet material 102 is
Since the sheet material 102 is weaker than 7, 108, an appropriate tension acts on the sheet material 102 so that the sheet material 102 is not loosened.

In this state, while the recording head 104 is moved from the near side to the far side in FIG. 15 by the carriage 105, ink is ejected in accordance with an image signal to record a predetermined width (recording width) on the sheet material 102. Do. Recording width W
Is m × p, where p is the pitch between the injection elements and m is the number of nozzles of the injection elements.

Each time recording of one line is completed, the lower transport roller 1
07, the sheet material 102 is sent out by the conveyance lower roller 107 by the conveyance upper roller 108 by the same amount W as the recording width, and the next line is recorded.

Recording is performed on the sheet material 102 by repeating the above operation, and when the recording of one sheet material 102 is completed, the sheet material 102 is
The paper is discharged onto the paper discharge tray 114 from the sheets 2 and 113. FIG. 17 shows an example of an image recorded on the sheet material 102.

Here, in the second reference example , as shown in FIG. 18, the pitch p between the ejection elements: 0.0635 mm The number of nozzles m ₁ of the ejection elements used for recording: 12
Eight pieces Recording width W (= m × p): 8.128 mm Transport amount L ₁ (= W) by the transport roller in one step:
8.128 mm Transport amount L ₂ by pulling roller in one step: L ₂ : 8.1
28 + 0.0635 = 8.1915 mm No. of nozzles m ₂ (m ₁ +1) of all ejection elements: 129
Nozzle.

Each time the recording of one line (width W) of the sheet material 102 by the 128 nozzles of the portion A of the ejection elements 129 nozzles of the recording head 104 close to the lower conveying roller 107 is completed, the recording width W is changed by the lower conveying roller 107. Same as L
₁ sent out.

When the recording in this state continues and the rear end of the sheet material 102 comes off the conveying upper and lower rollers 107 and 108, the sheet material 102 is conveyed by the pulling roller 112. At this time, the transport amount L ₂ (8.1915 mm) is
The pitch p between from the ejection element conveying distance L ₁ by 1
It is set so as to increase by 0.0635 mm for the pitch. Here, if the same recording as described above is continued, as shown in FIG.

[0068]

[Outside 1] Rear parts a ₁ comes to a position advanced to 128 paper feeding direction by the injection element 1 pitch without coming to the front end of the nozzle of the A portion. Therefore, in this state, 128 nozzles of the ejection element used for recording are shifted by one pitch in the paper feed direction.
The recording is performed using the nozzles of the unit, and the connection without blanks is performed. Here, the timing of switching the nozzles of the portion A and the portion B is determined in advance by setting the rear end of the sheet material 102 to the conveyance upper and lower rollers 107,
The step feed exiting from step 108 is determined based on the length of the sheet material.

In the second reference example , the transport rollers 107, 10
8 and the ejection element are close to each other, and there is only one step feed after the rear end of the sheet material 2 has come out of the conveyance rollers 107 and 108. Therefore, the number of nozzles of the ejection element is 128, the number of nozzles of the ejection element used for recording. In the case where the number of steps is increased by one nozzle, but the gap between the transport rollers 107 and 108 and the ejection element is wide, and the number of step feeds after the rear end of the sheet material 102 has passed through the transport rollers 107 and 108 is two or more times. Is equipped with a head having many nozzles for several minutes of the step feed, and a pulling roller 112,
The nozzles to be used may be moved one nozzle at a time in accordance with the number of times of conveyance at 113.

In the second reference example , the sheet material 10
If the length of the sheet material 2 is not constant, a sensor for detecting a sheet material
May be detected to determine the timing for changing the injection element to be used. In the second reference example , the transport amount L ₂ by the pulling roller 112 is smaller than the transport lower roller 107.
Conveying distance L ₁ has been only one pitch number setting the pitch p between even the injection elements than by, set many more pitches may be shifted by a pitch minutes which is set when shifting the ejection element used for recording .

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS. In the third reference example , pulling rollers 117 and 118 are provided upstream of the recording unit, and transport rollers 107 and
There are eight. The sheet material 102 first has a tension roller 117,
It is transported by 118 and stopped in the state of FIG.
The recording of the recording width W (8.128 mm) is performed by the nozzle of the portion C which is 128 nozzles on the downstream side among the ejection elements having nozzles. Then pulling rollers 118 and 117 by the transport amount _{L 3: 8.128mm-0.0635mm (=} 8.0
645 mm) (FIG. 21). Here is the nose of part C

[0072]

[Outside 2] It comes to a position on the upstream side by 0.0635 mm. Therefore, the next printing is performed with 128 nozzles in the D section shifted one nozzle upstream from the C section.

In the conveyance of the sheet material 102 in the next step, since the front end of the sheet material is sent immediately before the nip of the conveyance rollers 107 and 108, the conveyance amount is 8.128 mm.
Therefore, when the sheet material 102 is fed by the transport lower roller 107, as shown in FIG. 22, the ejection element used for printing is 128 nozzles of D and printing is performed up to the rear end of the sheet material 102.

In the third embodiment , the number of ejection elements is 129 nozzles. However, if the gap between the ejection element and the conveyance roller is large and several steps are required until the leading end of the sheet material enters the conveyance roller, the number of steps is set to 129 nozzles. It is preferable to provide a head having only a large number of nozzles and shift the nozzles to be used sequentially.

(Fourth Reference Example) A fourth reference example will be described with reference to FIGS. 4th
In the reference example , the recording head 104 is fixed to the main body at the time of recording, and the ejection element 11 is perpendicular to the paper feeding direction.
5 are lined up with m + 6 nozzles. When the sheet material 102 is continuously conveyed on the platen 106 by the conveyance rollers 107 and 108 and the tension rollers 112 and 113, FIG.
As shown in Fig. 4, the width of the injection element m in the E section is m × nozzle.
Recording of p (pitch between ejection elements) is performed. At this time, as shown in FIG. 8, before the sheet material 102 is fed by the conveying rollers 107 and 108, the sheet material 102 is displaced in a direction perpendicular to the paper feeding direction (the direction of the arrow) due to the curl of the sheet material 102 or the like. In this case, the displacement of the sheet material 102 is detected by a position sensor (not shown), and the ejection element used for recording is changed to the m nozzle indicated by F. In FIG. 25, the ejection elements shifted by one nozzle are used, but the shift amount may be changed according to the value detected by the sensor, and recording may be performed at the center of the sheet material 102.

As described above, by having a larger number of ejection elements than the number of ejection elements corresponding to the recording width, it is possible to select ejection elements to be used for recording in accordance with the state of the recording medium, and it is possible to select a sheet material. There is an effect that the recording position can be changed at the time of recording at the end to perform high-precision recording.

(Others) It should be noted that the present invention includes a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for discharging ink, particularly in an ink jet recording system. Although an apparatus having a recording head of a type in which a change in the state of ink is caused by the thermal energy has been described, according to this type, it is possible to increase the recording density and the definition.

The typical configuration and principle are described, for example, in US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recording information and providing a rapid temperature rise exceeding the nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat-acting surface of the recording head. Cause
As a result, bubbles in the liquid (ink) corresponding to this drive signal one-to-one can be formed, which is effective. By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, A configuration using U.S. Pat. No. 4,558,333 or U.S. Pat. No. 4,459,600, which discloses a configuration in which a heat acting portion is arranged in a bending region, is also included in the present invention. In addition, for multiple electrothermal transducers,
JP-A-59-123670 which discloses a configuration in which a common slit is used as a discharge portion of an electrothermal transducer, and JP-A-59-123670 which discloses a configuration in which an opening for absorbing a pressure wave of thermal energy corresponds to a discharge portion. The effect of the present invention is effective even in a configuration based on JP-A-138461. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

In addition, even in the case of the serial type as described above, the recording head fixed to the apparatus main body or the electric connection with the apparatus main body or the ink from the apparatus main body is attached to the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

It is preferable to add recovery means for the print head, preliminary auxiliary means, and the like provided as a configuration of the printing apparatus in the present invention since the effects of the present invention can be further stabilized. . To be more specific, capping means for the recording head, cleaning means, pressurizing or suction means, preheating means using an electrothermal transducer or another heating element or a combination thereof, and recording Performing a preliminary ejection mode for performing another ejection is also effective for performing stable printing.

The type and number of recording heads to be mounted are, for example, not only those provided for one color ink but also a plurality of inks having different recording colors and densities. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. Alternatively, the device may be provided with at least one of full colors by color mixture.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or below and which softens or liquefies at room temperature, or an ink jet system In general, the temperature of the ink itself is controlled within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Anything can be used. In addition, positively prevent the temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or use an ink that solidifies in a standing state to prevent evaporation of the ink. In any case, in any case, the ink is liquefied by the application according to the recording signal of the thermal energy, and the liquid ink is ejected, such as the one that already starts to solidify when it reaches the recording medium,
The present invention is also applicable to a case where an ink that liquefies for the first time by thermal energy is used. In such a case, the ink is held in a state of being held as a liquid or solid substance in the concave portion or through hole of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. Alternatively, it may be configured to face the electrothermal converter. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition to the above, the form of the ink jet recording apparatus of the present invention can be used not only as an image output terminal of an information processing apparatus such as a computer, but also as a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. It may take a form.

[0085]

As described above, according to the image recording apparatus of the present invention, it is possible to perform a proper recording operation even on the edge of the sheet material, and it is possible to perform high-precision recording. .

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of an image recording apparatus to which the present invention is applied.

FIG. 2 is a cross-sectional view of the image recording apparatus shown in FIG.

FIG. 3 is a diagram illustrating a state where a sheet material is stopped.

FIG. 4 is a block diagram showing a control unit of the image recording apparatus shown in FIG.

FIG. 5 is a diagram showing a relationship between a width corresponding to a sheet material of each size, the number of steps until the trailing end is detected, and a remaining amount.

FIG. 6 illustrates a case where each control is performed in the first embodiment.
FIG. 8 is a diagram illustrating a relationship between a remaining amount at a rear end and an error in recording and joining;

FIG. 7 is a flowchart illustrating a control procedure according to the first embodiment.

FIG. 8 is a flowchart showing a part of FIG. 7 in detail.

FIG. 9 is a diagram illustrating a schematic configuration of an image recording apparatus according to a first reference example .

FIG. 10 is a diagram illustrating a relationship between a width corresponding to a sheet material of each size, the number of steps until a trailing end is detected, and a remaining amount in the first reference example .

FIG. 11 is a diagram illustrating a relationship between a remaining amount at a rear end and an error in recording joining when each control is performed in the first reference example .

FIG. 12 is a flowchart illustrating a control procedure in the first reference example .

FIG. 13 is a flowchart showing a part of FIG. 12 in detail.

14 is a flowchart showing a part of FIG. 12 in detail.

FIG. 15 is a sectional view of an image recording apparatus according to a second reference example .

FIG. 16 is a diagram illustrating a recording head.

FIG. 17 is a diagram illustrating an example of a recorded image.

FIG. 18 is a diagram illustrating a schematic configuration of an image recording apparatus according to a second reference example .

FIG. 19 is a diagram illustrating a relationship between a conveyance state of a sheet material and a recording position.

FIG. 20 is a diagram illustrating a schematic configuration of an image recording apparatus according to a third reference example .

FIG. 21 is a diagram illustrating a relationship between a conveyance state of a sheet material and a recording position.

FIG. 22 is a diagram illustrating a relationship between a sheet material conveyance state and a recording position.

FIG. 23 is a diagram illustrating a schematic configuration of an image recording apparatus according to a fourth reference example .

24 is a plan view showing a relationship between a recording head and a sheet material in the image recording apparatus shown in FIG.

FIG. 25 is a plan view illustrating a relationship between a recording head and a sheet material in the image recording apparatus illustrated in FIG. 23;

FIG. 26 is a sectional view of a conventional image recording apparatus.

FIG. 27 is a diagram illustrating a recording head.

FIG. 28 is a diagram illustrating a schematic configuration of the image recording apparatus illustrated in FIG. 26;

[Explanation of symbols]

 4 Recording head 7, 8 Conveying vertical roller 12, 13 Pulling vertical roller 17 Paper width sensor 19 Paper sensor

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI B41J 19/76 B41J 3/04 103B (56) References JP-A-60-4088 (JP, A) JP-A-61-249782 ( JP, A) JP-A-3-234575 (JP, A) JP-A-1-125648 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 29/50 B41J 2/01 B41J 2/05 B41J 11/42 B41J 19/76

Claims (4)

(57) [Claims] 1. A head mounting means for mounting a recording head for recording an image on a sheet material, a first conveying means for conveying a sheet material upstream of the recording head, and a downstream side of the recording head. And a second transport unit that transports the sheet material by a transport amount different from the transport amount of the first transport unit, wherein a predetermined width is recorded on the sheet material by the recording head. An image recording apparatus that performs recording by sequentially repeating step conveyance of a sheet material having a constant width by a conveyance unit and the second conveyance unit; a first detection unit that detects a width of the sheet material; and the first conveyance unit. A second detecting means for detecting a trailing end of the sheet material conveyed by the first conveying means and the second conveying means on the upstream side of; a width of the sheet material detected by the first detecting means; Writing on sheet material A determination unit configured to determine which standard size the sheet material is based on the number of times of step conveyance until the trailing edge of the sheet material is detected by the second detection unit after the start of recording, Control means for determining the remaining amount of the trailing end of the sheet material from the standard size of the material, and changing the amount of conveyance by the second conveying means and the recording area of the recording head according to the amount of remaining trailing end. An image recording apparatus, characterized in that: 2. The printing head according to claim 1, wherein the printing head includes a plurality of printing elements arranged substantially parallel to a sheet conveying direction, and selects a printing element to be used for printing from the plurality of printing elements. The image recording apparatus according to claim 1, wherein a recording area of the recording head is changed by the following. 3. The image recording apparatus according to claim 1, wherein the recording head is an inkjet recording head capable of discharging ink. 4. The image recording apparatus according to claim 3, wherein the inkjet recording head includes an electrothermal converter that generates thermal energy used for discharging ink.